The objective of this multicenter trial is to evaluate the safety, immunogenicity and efficacy of a recombinant herpes simplex virus vaccine in adults. Adult subjects discordant for HSV-2 infection are enrolled and susceptible subjects are randomized to receive 3 doses of a recombinant vaccine or placebo. Follow-up evaluations over 18 months will be conducted and the immunologic response of the subjects compared. Frequency of infection between vaccine recipients and placebo controls will be compared.